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diff --git a/sys/net/netmap.h b/sys/net/netmap.h
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+/*
+ * Copyright (C) 2011 Matteo Landi, Luigi Rizzo. All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * 
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ * 
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the
+ *      distribution.
+ * 
+ *   3. Neither the name of the authors nor the names of their contributors
+ *      may be used to endorse or promote products derived from this
+ *      software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY MATTEO LANDI AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTEO LANDI OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * $FreeBSD$
+ * $Id: netmap.h 9662 2011-11-16 13:18:06Z luigi $
+ *
+ * This header contains the definitions of the constants and the
+ * structures needed by the ``netmap'' module, both kernel and
+ * userspace.
+ */
+
+#ifndef _NET_NETMAP_H_
+#define _NET_NETMAP_H_
+
+/*
+ * --- Netmap data structures ---
+ *
+ * The data structures used by netmap are shown below. Those in
+ * capital letters are in an mmapp()ed area shared with userspace,
+ * while others are private to the kernel.
+ * Shared structures do not contain pointers but only relative
+ * offsets, so that addressing is portable between kernel and userspace.
+ *
+ * The 'softc' of each interface is extended with a struct netmap_adapter
+ * containing information to support netmap operation. In addition to
+ * the fixed fields, it has two pointers to reach the arrays of
+ * 'struct netmap_kring' which in turn reaches the various
+ * struct netmap_ring, shared with userspace.
+
+
+ softc
++----------------+
+| standard fields|
+| if_pspare[0] ----------+
++----------------+       |
+                         |
++----------------+<------+
+|(netmap_adapter)|
+|                |                             netmap_kring
+| tx_rings *--------------------------------->+-------------+
+|                |       netmap_kring         | ring *---------> ...
+| rx_rings *---------->+--------------+       | nr_hwcur    |
++----------------+     | ring    *-------+    | nr_hwavail  |
+                       | nr_hwcur     |  |    | selinfo     |
+                       | nr_hwavail   |  |    +-------------+
+                       | selinfo      |  |    |     ...     |
+                       +--------------+  |  (na_num_rings+1 entries)
+                       |    ....      |  |    |             |
+                    (na_num_rings+1 entries)  +-------------+
+                       |              |  |
+                       +--------------+  |
+                                         |      NETMAP_RING
+                                         +---->+-------------+
+                                             / | cur         |
+   NETMAP_IF  (nifp, one per file desc.)    /  | avail       |
+    +---------------+                      /   | buf_ofs     |
+    | ni_num_queues |                     /    +=============+
+    |               |                    /     | buf_idx     | slot[0]
+    |               |                   /      | len, flags  |
+    |               |                  /       +-------------+
+    +===============+                 /        | buf_idx     | slot[1]
+    | txring_ofs[0] | (rel.to nifp)--'         | len, flags  |
+    | txring_ofs[1] |                          +-------------+
+  (num_rings+1 entries)                     (nr_num_slots entries)
+    | txring_ofs[n] |                          | buf_idx     | slot[n-1]
+    +---------------+                          | len, flags  |
+    | rxring_ofs[0] |                          +-------------+
+    | rxring_ofs[1] |
+  (num_rings+1 entries)
+    | txring_ofs[n] |
+    +---------------+
+
+ * The NETMAP_RING is the shadow ring that mirrors the NIC rings.
+ * Each slot has the index of a buffer, its length and some flags.
+ * In user space, the buffer address is computed as
+ *	(char *)ring + buf_ofs + index*MAX_BUF_SIZE
+ * In the kernel, buffers do not necessarily need to be contiguous,
+ * and the virtual and physical addresses are derived through
+ * a lookup table. When userspace wants to use a different buffer
+ * in a location, it must set the NS_BUF_CHANGED flag to make
+ * sure that the kernel recomputes updates the hardware ring and
+ * other fields (bus_dmamap, etc.) as needed.
+ *
+ * Normally the driver is not requested to report the result of
+ * transmissions (this can dramatically speed up operation).
+ * However the user may request to report completion by setting
+ * NS_REPORT.
+ */
+struct netmap_slot {
+	uint32_t buf_idx; /* buffer index */
+	uint16_t len;	/* packet length, to be copied to/from the hw ring */
+	uint16_t flags;	/* buf changed, etc. */
+#define	NS_BUF_CHANGED	0x0001	/* must resync the map, buffer changed */
+#define	NS_REPORT	0x0002	/* ask the hardware to report results
+				 * e.g. by generating an interrupt
+				 */
+};
+
+/*
+ * Netmap representation of a TX or RX ring (also known as "queue").
+ * This is a queue implemented as a fixed-size circular array.
+ * At the software level, two fields are important: avail and cur.
+ *
+ * In TX rings:
+ *	avail	indicates the number of slots available for transmission.
+ *		It is decremented by the application when it appends a
+ *		packet, and set to nr_hwavail (see below) on a
+ *		NIOCTXSYNC to reflect the actual state of the queue
+ *		(keeping track of completed transmissions).
+ *	cur	indicates the empty slot to use for the next packet
+ *		to send (i.e. the "tail" of the queue).
+ *		It is incremented by the application.
+ *
+ *   The kernel side of netmap uses two additional fields in its own
+ *   private ring structure, netmap_kring:
+ *	nr_hwcur is a copy of nr_cur on an NIOCTXSYNC.
+ *	nr_hwavail is the number of slots known as available by the
+ *		hardware. It is updated on an INTR (inc by the
+ *		number of packets sent) and on a NIOCTXSYNC
+ *		(decrease by nr_cur - nr_hwcur)
+ *		A special case, nr_hwavail is -1 if the transmit
+ *		side is idle (no pending transmits).
+ *
+ * In RX rings:
+ *	avail	is the number of packets available (possibly 0).
+ *		It is decremented by the software when it consumes
+ *		a packet, and set to nr_hwavail on a NIOCRXSYNC
+ *	cur	indicates the first slot that contains a packet
+ *		(the "head" of the queue).
+ *		It is incremented by the software when it consumes
+ *		a packet.
+ *
+ *   The kernel side of netmap uses two additional fields in the kring:
+ *	nr_hwcur is a copy of nr_cur on an NIOCRXSYNC
+ *	nr_hwavail is the number of packets available. It is updated
+ *		on INTR (inc by the number of new packets arrived)
+ *		and on NIOCRXSYNC (decreased by nr_cur - nr_hwcur).
+ *
+ * DATA OWNERSHIP/LOCKING:
+ *	The netmap_ring is owned by the user program and it is only
+ *	accessed or modified in the upper half of the kernel during
+ *	a system call.
+ *
+ *	The netmap_kring is only modified by the upper half of the kernel.
+ */
+struct netmap_ring {
+	/*
+	 * nr_buf_base_ofs is meant to be used through macros.
+	 * It contains the offset of the buffer region from this
+	 * descriptor.
+	 */
+	const ssize_t	buf_ofs;
+	const uint32_t	num_slots;	/* number of slots in the ring. */
+	uint32_t	avail;		/* number of usable slots */
+	uint32_t	cur;		/* 'current' r/w position */
+
+	const uint16_t	nr_buf_size;
+	uint16_t	flags;
+	/*
+	 * When a ring is reinitialized, the kernel sets kflags.
+	 * On exit from a syscall, if the flag is found set, we
+	 * also reinitialize the nr_* variables. The kflag is then
+	 * unconditionally copied to nr_flags and cleared.
+	 */
+#define	NR_REINIT	0x0001		/* ring reinitialized! */
+#define	NR_TIMESTAMP	0x0002		/* set timestamp on *sync() */
+
+	struct timeval	ts;		/* time of last *sync() */
+
+	/* the slots follow. This struct has variable size */
+	struct netmap_slot slot[0]; /* array of slots. */
+};
+
+
+/*
+ * Netmap representation of an interface and its queue(s).
+ * There is one netmap_if for each file descriptor on which we want
+ * to select/poll.  We assume that on each interface has the same number
+ * of receive and transmit queues.
+ * select/poll operates on one or all pairs depending on the value of
+ * nmr_queueid passed on the ioctl.
+ */
+struct netmap_if {
+	char ni_name[IFNAMSIZ]; /* name of the interface. */
+	const u_int ni_version;	/* API version, currently unused */
+	const u_int ni_num_queues; /* number of queue pairs (TX/RX). */
+	const u_int ni_rx_queues;  /* if zero, use ni_num_queues */
+	/*
+	 * the following array contains the offset of the
+	 * each netmap ring from this structure. The first num_queues+1
+	 * refer to the tx rings, the next n+1 refer to the rx rings.
+	 * The area is filled up by the kernel on NIOCREG,
+	 * and then only read by userspace code.
+	 * entries 0..ni_num_queues-1 indicate the hardware queues,
+	 * entry ni_num_queues is the queue from/to the stack.
+	 */
+	const ssize_t	ring_ofs[0];
+};
+
+#ifndef IFCAP_NETMAP	/* this should go in net/if.h */
+#define	IFCAP_NETMAP	0x100000
+#endif
+
+#ifndef NIOCREGIF	
+/*
+ * ioctl names and related fields
+ *
+ * NIOCGINFO takes a struct ifreq, the interface name is the input,
+ *	the outputs are number of queues and number of descriptor
+ *	for each queue (useful to set number of threads etc.).
+ *
+ * NIOCREGIF takes an interface name within a struct ifreq,
+ *	and activates netmap mode on the interface (if possible).
+ *
+ * NIOCUNREGIF unregisters the interface associated to the fd.
+ *
+ * NIOCTXSYNC, NIOCRXSYNC synchronize tx or rx queues,
+ *	whose identity is set in NIOCREGIF through nr_ringid
+ */
+
+/*
+ * struct nmreq overlays a struct ifreq
+ */
+struct nmreq {
+	char		nr_name[IFNAMSIZ];
+	uint32_t	nr_version;	/* API version (unused) */
+	uint32_t	nr_offset;	/* nifp offset in the shared region */
+	uint32_t	nr_memsize;	/* size of the shared region */
+	uint32_t	nr_numslots;	/* descriptors per queue */
+	uint16_t	nr_numrings;
+	uint16_t	nr_ringid;	/* ring(s) we care about */
+#define NETMAP_HW_RING	0x4000		/* low bits indicate one hw ring */
+#define NETMAP_SW_RING	0x2000		/* we process the sw ring */
+#define NETMAP_NO_TX_POLL	0x1000	/* no gratuitous txsync on poll */
+#define NETMAP_RING_MASK 0xfff		/* the ring number */
+};
+
+/*
+ * default buf size is 2048, but it may make sense to have
+ * it shorter for better cache usage.
+ */
+
+#define	NETMAP_BUF_SIZE	(2048)
+#define NIOCGINFO	_IOWR('i', 145, struct nmreq) /* return IF info */
+#define NIOCREGIF	_IOWR('i', 146, struct nmreq) /* interface register */
+#define NIOCUNREGIF	_IO('i', 147) /* interface unregister */
+#define NIOCTXSYNC	_IO('i', 148) /* sync tx queues */
+#define NIOCRXSYNC	_IO('i', 149) /* sync rx queues */
+#endif /* !NIOCREGIF */
+
+#endif /* _NET_NETMAP_H_ */